1 Field of the Invention
The present invention relates to a new photographic film format, and to cameras and other photographic apparatus adapted to receive film having such a format.
2. Description of the Prior Art
Distinctions have been made between those film housings referred to as magazines, cartridges, cassettes, etc. But, for the purpose of this disclosure and the appended claims, the term "magazine" is intended to refer to any housing for roll film which is loadable into photographic apparatus.
Film housed in a magazine is usually provided with a leader which extends from the magazine's film exit passageway. Generally, the leader is either attached to a take-up core in the magazine itself, or is intended to be attached to a take-up core in the photographic apparatus. When the take-up core is rotated, the film is pulled through the exposure position of the photographic apparatus.
Such arrangements, wherein the film is transported by rotation of a take-up core, lend themselves to metering apparatus which temporarily disables the transport mechanism when a perforation is detected at a predetermined location along the film path. Such metering apparatus is commonly used in cameras adapted to receive film which has one perforation per image area and no perforations in the leader, such as size 126 and size 110 film. The absence of perforations in the leader permits the leader to be advanced through the gate without metering the camera.
While such arrangements are suitable for double-ended magazines or for cameras wherein the leader is attachable to an internal take-up core, some cameras, such as shown in U.S. Pat. No. 2,559,892, are adapted to receive a single-ended magazine without attachment of the leader to any take-up core. The camera shown in that patent advances the film into a coreless take-up chamber by a set of claws which enters film perforations in both the leader and the image portion of the filmstrip. If a metering mechanism is activated by the presence of such perforations at a predetermined position in the camera, the presence of perforations in the leader would cause the metering mechanism to activate before the image portion of the filmstrip has been advanced to the camera's exposure position.